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This study proposes a mathematical model based on a differential mass balance for predicting the evaporation and permeation profiles of fragrance systems applied to skin. For that, three fragrance systems (α-pinene, limonene, and linalool diluted in ethanol) were tested, and the experimental assays were performed using a Franz diffusion cell with porcine skin as a barrier. Both finite and infinite doses were studied: the first one to simulate a realistic scenario and the second one to obtain experimental skin permeation coefficients values. The liquid concentrations of the odorants in the receptor chamber were assessed using a dynamic headspace coupled to gas chromatography with a flame ionization detector, and the gas concentrations (donor chamber) of the odorants were achieved by gas chromatography with a flame ionization detector. Our model described well both the release and permeation of all tested fragrance systems. In conclusion, we are proposing a relatively robust tool for predicting the performance of fragrance systems from skin, allowing the development of novel and/or most efficient fragrance formulations.

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This study aims to find the best conditions for the extraction of Zingiber officinale essential oil using the supercritical fluid extraction (SFE), steam distillation (SD) and hydrodistillation (HD) techniques, regarding the maximum oil yield. For the HD technique is evaluated the best ratio between plant mass and water volume and for SFE and SD the pressure condition was investigated. Principal Component Analysis (PCA) was used to evaluate the similarity between the composition of the essential oil in different pressures and extraction methods. The experimental extraction curve was plotted and three different mathematical models were used to fit the data for SD and SFE methods, obtaining the relevant mass transfer parameters. The essential oil compounds were identified by gas chromatography coupled with mass spectrometry (GC-MS), being αzingiberene the main component with different contents (from 11.9 to 28.9%). The best condition for the SFE HIGHLIGHTS  Ginger essential oil was extracted by SFE, SD and HD, modelling was also performed.  Different pressures (SD and SFE) and water volumes (HD) were investigated.  The extraction products were analyzed by GC/MS.  PCA was performed, geranial and α-zingiberene have the greatest covariance.